This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This research is to identify glycosylation sites of thioester-containing proteins which are purified by Dr. Baxter by simultaneous protease (Trypsin, Lys-C) and PNGase F digestions and 18O labeling of asparagines residue carrying glycans. The peptide sample was loaded onto a capillary column packed with C18 and eluted over 160 min with a flow of 200 nL/min using a linear gradient of 5 ~ 95% of 80% acetonitrile in 0.1 % formic acid. The eluted peptides were analyzed by nanoelectrospray ionization mass spectrometry (NSI-MS) using a LTQ-MS (Thermo Finnigan). TurboSequest (Bioworks 3.3, Thermo Finnigan) was used for MS/MS spectra searching against a TEP 1 database. The research project was completed in 2008.